Word: megahertz
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...that have survived the current chill between Washington and Moscow. One reason: it requires no transfers of hardware or technology. The only tools the satellites have in common is their electronic "language": they must all be tuned to the standard international radio frequencies for distress calls (121.5 and 243 megahertz). Though the U.S. and Canada tested such electronics on earlier American satellites, the first true U.S. SARSAT will not become operational until next February, when the National Oceanographic and Atmospheric Administration's latest Tiros weather satellite goes into orbit...
...experiments, LeVeen, a surgeon who also teaches at Brooklyn's Downstate Medical Center, employed radio-frequency generators that operated at 13.56 megahertz, in the frequency range used by short-wave broadcasters. The signals were sent into the body by electrodes or other devices attached directly to the skin immediately above the tumors. The doses, lasting up to 30 minutes, never exceeded 25 watts-the power drawn by a small light bulb-per square inch. The lightly sedated patients generally felt no pain and did not suffer serious damage to skin or other tissue. Nonetheless, the radiation was strong enough...
...communications system. Known as a signal processor, it accepted the astronauts' voices as well as 900 other signals-telemetric data on heartbeats, for example, pressure readings in the cabin, data from the computers-and imposed them on a single "carrier" frequency of 2,282.5 megahertz. An amplifier increased the signal's power from half a watt to 20 watts, the strength of a small ham-radio transmitter. The 26-in. dish antenna, perched atop the LM, then beamed the signal to earth...
...unit, which shares its channels with car phones, operates in the 150-megahertz band. It has an output of 25 watts, which makes it normally serviceable within 30 miles of a mobile operator. No matter how distressing the conversation turns out to be, profanity is not advisable. The FCC prohibits swearing, and mobile operators are quick to interrupt when the language turns blue...
...activity among U.S. scientists. Focusing Cornell University's giant radio telescope near Arecibo, Puerto Rico, on the one pulsar whose position was given by the British, Astronomer Frank Drake confirmed the rapid, regular signal and discovered that it was ten times as powerful at 111 MH (for megahertz: 1,000,000 cycles per second) than at any other frequency. "This has been the biggest bombshell that I can remember in radio astronomy," he says. Caltech Astronomer Maarten Schmidt, who discovered the strange nature of quasars, calls the finding "fantastic, incredible...